re: Estimating Time

I am afflicted with the same problem.

I am sure I could cut my “overtime” by at least half if I actually plan everything on paper before starting the project and stick to plan.

My biggest problem is I think it through quite a bit in my head. In fact for difficult project I go through the motion and figuring out problem area every now and then for a few day and, sometimes, take quick notes.
When I am ready, that’s the time I have to postpone the execution for either the kids have a project or my wife had something planed that I had said “sure” to…

When I actually start the project, I barely look through the notes, if I have not lost them.
The first “on the fly” modification usually comes within the hour most of the time because I cut the wrong piece. From there: finish time= ETA x 10 to 15

But for me it is all a hobby, no deadline pressure besides the one I create.